removing piston pieces from crankcase

[burhead]

Is there a recomended method for removing particles of a piston from the crankcase. I bought a banshee that was running on one cylinder and was tearing it down today. Both pistons were pitted up pretty badly and some of the top rings were missing from both pistons. The right side was burned and pitted pretty good, the left was mostly pitted. I would expect most of it went out the exhaust but as I was lifting one of the cylinders off I think a piece of the piston might have broke off and fell down in the crank. Now when I spin the crank sometimes it will catch alittle on the piece that is in there. So is there a good method for flushing it out. I was thinking of pulling the drainplug and running some premix gas through it and seeing what comes out. Anyone got any better suggestions before I split this thing open and spend a bunch more money.

[Rodneya]

The drain plug is for the transmission only. The crank case is totally separate.

splitting the cases is the only way you can be certain it is all clean. If you are certain it is only 1 piece, it may come out with the motor upside down. But you wont really know if you got everything.

[Martinm210]

Is there a recomended method for removing particles of a piston from the crankcase. I bought a banshee that was running on one cylinder and was tearing it down today. Both pistons were pitted up pretty badly and some of the top rings were missing from both pistons. The right side was burned and pitted pretty good, the left was mostly pitted. I would expect most of it went out the exhaust but as I was lifting one of the cylinders off I think a piece of the piston might have broke off and fell down in the crank. Now when I spin the crank sometimes it will catch alittle on the piece that is in there. So is there a good method for flushing it out. I was thinking of pulling the drainplug and running some premix gas through it and seeing what comes out. Anyone got any better suggestions before I split this thing open and spend a bunch more money.

 

There's really not any good sure method. I've tried flushing with WD-40 on a chainsaw until I thought it was pretty clean, then tore it down to see. It didn't look good, chances are any flushing is just going to flush it into the bearings further.

 

Only real way is to part the cases, but the good news is...you can replace those seals while you're at it. It's good insurance to ensure you don't have a crankcase air leak.

 

Also, the banshee is really easy, no special tools other than a flywheel puller and a 30mm socket. Almost all other case splittings I've done have required heating and pressing of bearings, etc. On those you also need at least and arbor press.

 

Once you've done it once, it only takes a couple of hours to split one.

[burhead]

i knew this was going to be bad news when I saw the pistons. I am pretty mechanically inclined but this winter I tried splitting the cases on a polaris 2 stroke and ended up ruining the crack because I didnt have the proper tools. My biggest challenge is going to be time because I dont have much of it to mess with these things. The polaris was a boat anchor anyways I just wanted to seperate it to see what I could salvage. It looks like the banshees split hrizontally instead of vertically like the polaris'. Is that correct? Anyways I already have a guy lined up to do the topend. Ritter cycle does all my polaris topends so maybe I will see what he charges to go through the bottom end as well. What does it generally cost to have someone do the bottomend of one of these? Any recommendations on who to send it to? I dont trust the local shops in my area to touch any of my bikes so that is not an option. They all have a bunch of lawn mower mechanics working for them and they get 70 bucks an hour to screw stuff up.

[burhead]

Is there a drain for the crank case. I went ahead and poured some premix in before I saw the post. Now I cant get it to drain. I guess I will be pulling the motor tomorrow to dump it out and see what comes out.

[burhead]

well I pulled the motor today and dumped the premix I had in there and strained it through a screen. Nothing major came out. I ran premix through it several times and it was clear when I was done. I am almost positive this thing was sucking sand when it went because the kid that had it before me never bothered to oil the filter before he rode it. So I am on the fence if I am going to go through the bottom end or not.